What if my bank doesn't support Apple Pay?

You have to keep asking them or change banks.

Every bank provides you with those numbers I mentioned. You can use them to transfer money, make direct payment/deposit, auto payment/deposit. Use them for whatever systems that request them—Apple Card requires them. And I’m pretty sure the bank doesn’t care.

I know what those numbers are for. I have been banking for some time now (close to 30 yrs). The original question ONLY mentions Apple Pay. No mention of transfers, no mention of Apple Card, no mention of anything at all except that the bank does not accept Apple Pay. Granted I could have used batter wording when I asked what those numbers were for. However, only the OP can clarify what they are asking about. I try not to answer beyond what is being asked most times especially on questions this cut and dried.

Okay, I understand. If the OP is talking about using Apple Pay (Not Apple Card) using certain banking card that AP doesn’t recognize, Then why bother using the Wallet app at all. Yes, that’s right. My bad...if we’re not talking Apple Card.

I believe you don’t have to tell your bank. You just get the routing number and checking account number from your monthly statement.

It's on every check.

What are those numbers good for if the bank does not support Apple Pay?

(If I am missing something, I apologize)

Those numbers are for check routing. They've been around for a hundred years.

The OP was asking about Apple Pay bank support from their bank. I know what those numbers are for but not in relation to the OPs question.

I am unaware of any bank in the country that does not support ACH money transfers.

...and also, Apple Pay does require those numbers. I don’t know what the other user is talking about.

If the bank is not on the list for Apple Pay (Apple Pay participating banks - Apple Support) those numbers are worthless.